Apparatus and process for making prosthetic suction sleeve

ABSTRACT

The method of making a tubular member having a continuous and uninterrupted cured elastomeric resin coating on an outer surface of the member includes forming a continuous uninterrupted tubular layer of uncured elastomeric resin and drawing the resin layer against the surface of the tubular member to be coated by applying suction between the resin layer and the surface of the tubular member so that the resin adheres to the surface of the tubular member. The elastomeric resin may then be cured to produce the final product. Apparatus for carrying out the process is disclosed and includes, in sequence, a coating zone including a sub-atmospheric chamber, a heating zone and a feed mechanism for advancing the tubular member relative to the coating and heating zones. A method is also disclosed for molding a distal end cap on an open end of a length of a preformed tubular sleeve member that may be used for prosthetic applications. A process is also disclosed for molding a sleeve member having prosthetic applications using male and female die elements used to distribute uncured elastomer resin as a layer on a tubular elasticized fabric sleeve element.

CROSS-REFERENCE TO PROVISIONAL APPLICATION

[0001] The benefit of Provisional application Ser. No. 60/189,478 filedMar. 15, 2000 is hereby claimed under 35 U.S.C. §119(e)(1).

1. FIELD OF THE INVENTION

[0002] This invention relates to the process and apparatus for makingprosthetic suction liners and coating tubular substrates.

2. BACKGROUND OF THE INVENTION

[0003] Prosthetic suction liners have been described in U.S. Pat. No.4,923,474 granted to Klasson and Kristinsson on May 8, 1990; U.S. Pat.No. 5,728,168 granted Mar. 17, 1998 to Laghi et al.; and U.S. Pat. No.5,830,237 granted to Kania Nov. 3, 1998.

[0004] The original suction liner as described in U.S. Pat. No.4,923,474 was formed of a silicone elastomer and was adapted to therolled over residual limb of a prosthetic user in a manner fullydescribed in the patent.

[0005] The manufacturing process for making suction liners with a fabricexterior covering adhered to one or more cured elastomer inner layerstypically involves multiple injection molding procedures and possiblylaminating procedures that are designed to build-up the various layersconstituting the suction liner. Obtaining an intimate bond between thesilicone and fabric layers is particularly important, particularly whenit is necessary to maintain full elasticity of the suction liner toenable it to closely fit over and conform to a residual limb of aprosthetic user.

[0006] The process is more complicated when a distal prostheticconnector fitting must be incorporated in the distal end of the suctionliner, particularly when an injection molding procedure is utilized.

[0007] Injection molding procedures are time consuming and requirecomplex equipment to ensure accurate shapes and thicknesses of varioussize suction liners. Injection molding thick, soft elastomeric layers onthe inner surfaces of suction liners also present a challenge usinginjection molding techniques.

[0008] Prior art procedures for continuously coating tubular substrateswith a cured elastomer coating or film involve many different proceduresthat tend to be expensive and time consuming. It is highly desirable tocontinuously coat tubular substrates with an elastomer layer intimatelybonded or adhered to the substrate in a convenient, low cost procedure,particularly where the substrate is an elasticized, porous fabric.

BRIEF SUMMARY OF THE INVENTION

[0009] The invention relates to a process for forming a generallyconcial, close ended suction liner having a fabric outer covering, athin cured silicone elastomer coating preferably provided on theinterior surface of the fabric and a cured silicone elastomer liningadjacent the intermediate silicone coating. The prosthetic suction lineris formed with a distal end cap in which a prosthetic “umbrella”connector is embedded at the distal end of the suction liner using aprocess according to the invention described herein. The prostheticconnector is exposed in a central portion to provide access to aprosthetic pin connector in a conventional manner. An optionalreinforcement layer may be embedded in the innermost silicone elastomerlayer using the inventive process to restrict axial elongation of thedistal end portion of the suction liner while permitting lateraldistension of the liner material in that portion of the liner in whichthe reinforcement material is embedded in the silicone elastomer layer.

[0010] One aspect of the inventive process involves providing acylindrical tubular length of elasticized fabric that is stretchableboth longitudinally and laterally relative to the axis of the tube;coating the inner surface of the fabric tube with a continuous, thincured silicone elastomer that partially penetrates and adheres stronglyto the fabric but does not extend through the full fabric thickness;optionally attaching a tubular length of reinforcement matrix materialto one end of the coated tubularfabric; placing the tubular length offabric and the optional reinforcement in a molding device; placing theumbrella prosthetic connector element in the molding device; molding andcuring a silicone elastomer distal end cap over one end of the tubularlength of coated fabric and the optional reinforcement matrix so as toembed the umbrella prosthetic connector in the distal end cap siliconematerial while bonding the distal end cap to the end of the tubularlength of fabric and the optional reinforcement matrix; removing thetubular length of fabric with the molded distal end cap from the moldingdevice and inserting a premeasured quantity of uncured silicone resinthat will form an inner layer of the liner into the closed end of thefabric tube and end cap; inserting the fabric tube with the premeasuredquantity of uncured resin and the distal end cap into a female moldcavity having a defined peripheral contour corresponding to a desiredouter peripheral contour of the prosthetic suction liner; advancing amale mold member having an external contour corresponding to the desiredinner contour of the suction liner into the interior of the tubularfabric and distal end cap assembly from its open end to cold forge theuncured silicone elastomer over the full length of a cavity definedbetween the male and female molds to fully form the innermost siliconeelastomer layer to a desired contour and thickness and carrying out apreliminary cure of the inner most silicone elastomer in the forgingdevice; removing the formed assembly of tubular fabric and partiallycured silicone elastomer layer from the forming device and fully curingthe innermost silicone elastomer layer.

[0011] Apparatus for carrying out the process includes a continuous filmcasting device configured to continuously cast an uncured elastomer filmcoating on a tubular substrate using sub-atmospheric suction to draw thefilm to the surface of the fabric substrate; and a heater in series withthe continuous film casting apparatus arranged to cure the castelastomer film continuously during the coating process to therebyproduce a continuous tubular length of substrate coated on one surfacethereof with a cured elastomer film.

[0012] When the apparatus is used to apply an elastomer coating to aporous material such as an elasticized fabric, the suction appliedduring casting of the uncured elastomer film is adjusted so that thefilm partially embeds itself in the intersices or pores of the fabricwhile avoiding complete penetration of the elastomer throughout thefabric thickness. This leaves the opposed surface of the fabric free ofelastomer while producing a continuous sealing film of elastomer on thefirst surface of the tubular length of fabric.

[0013] During curing, the tension applied to the coated substrate isadjusted to produce optimum qualities for the coated length of substratethat are appropriate for the thus produced product or any subsequent useof the coated substrate in a manufacturing procedure in which the coatedsubstrate is formed into an end product.

[0014] The thus coated tubular length of substrate may be reversed withthe cured elastomer coating on the inside of the substrate. The tubularcoated substrate may then be cut to lengths corresponding approximatelyto individual lengths of products to be made with the coated lengths ofsubstrate and a tubular matrix of reinforcement material may be attachedto one end of the end of the tubular length of substrate for use, forexample, in a prosthetic suction liner.

[0015] As described previously, a distal end cap may be molded to theone end of a tubular length of coated elasticized fabric substrate witha prosthetic connector fitting or umbrella embedded in the distal endcap.

[0016] In a specific example wherein it is desired to use such acontinuous coated tubular substrate in a process for making a prostheticsuction liner, the substrate comprises a tubular elasticized fabric suchas circular knit fabric that is distensible both lengthwise andwidthwise and the elastomer is constituted of a silicone elastomerformulated so that it may be cast as a continuous film in its uncuredcondition in a temperature range that is practical. The coated fabricmaintains its elasticity due to the elasticity of the silicone elastomerin its cured condition. The surface of the cured silicone film may beleft in a somewhat tacky condition so as to be readily bondable to asubsequent silicone elastomer layer.

[0017] The cold forging apparatus includes a female die that preferablyincludes suction devices to draw the fabric tube into intimate contactwith the interior walls of the female die prior to the advancement ofthe male member into the female die. The male die member formed inaccordance with a desired inner profile of the innermost siliconeelastomer layer of the suction liner, is advanced into the uncuredsilicone elastomer previously deposited into the closed end of thefabric and distal end cap assembly so the elastomer is forced to flowlongitudinally through a cavity that is formed between the female dieand the male die member from the closed end of the suction liner to theproximal open end thereof. The procedure may be referred to as a coldforging process for convenience.

[0018] The rate of advancement of the male die member is controlled topermit complete flow of the uncured silicone elastomer throughout thecavity provided between the male and female die members, particularlywhen the gap between the male and female die members varies along thelength of the molding device.

[0019] A guide pin may be inserted into the prosthetic connector elementembedded in the distal end cap of the pre-formed tubular length ofcoated fabric, distal end cap and prosthetic connector. The female dieincludes an aperture at its distal end arranged to receive the guide pinto thereby center and locate the length of coated fabric and distal endcap in the female die before the male die member is advanced into thefemale die to cold forge the uncured silicone elastomer resin into thedie cavity between the male and female die members.

[0020] The male and female dies may be heated to perform a preliminarycuring of the silicone elastomer of the silicone elastomer in the moldcavity before the laminated assembly of elasticized fabric, thin coatingof silicone elastomer and final inner layer of silicone elastomer areremoved from the die.

[0021] The process and apparatus constituting the inventive subjectmatter will be described in more detail in the drawings and descriptionthat follow.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022]FIG. 1 is a longitudinal section view of a suction liner formed inaccordance with the process according to the present invention;

[0023]FIG. 2 is a distal end view of the suction liner shown in FIG. 1;

[0024]FIG. 3 is a section view taken along line III-III of FIG. 1;

[0025]FIG. 4 is an enlarged view of FIG. 3 to show the details of thesuction liner side wall;

[0026]FIG. 5 shows a tubular sealing sleeve formed by using a coatingprocess according to the present invention;

[0027] FIGS. 6-10 show the geometry of the cured silicone elastomerinner layer of a suction sleeve shown in FIG. 1;

[0028]FIG. 11 is a schematic view of a flat section of elasticizedfabric in process of being folded and stitched to form a length oftubular elasticized fabric;

[0029]FIG. 12 schematically shows a continuous coating system forapplying a cast elastomer film onto one surface of the tubular substratein a continuous process;

[0030]FIGS. 13 and 14 show details of the apparatus illustrated in FIG.12;

[0031]FIG. 15 shows a reinforcement matrix stitched to one end of alength of elasticized fabric that has been coated with a continuouscured silicone elastomer film;

[0032]FIG. 16 shows a molding device for molding a distal end cap ontothe length of tubular elasticized fabric that has been previously coatedand provided with a tubular length of reinforcement matrix at one endthereof;

[0033] FIGS. 17-21 schematically illustrate a procedure for molding adistal end cap onto the tubular fabric using the apparatus shown in FIG.17;

[0034]FIG. 22 is a detailed view showing the distal end of an assemblyof elasticized tubular fabric coated with a continuous siliconeelastomer film on the inner surface thereof, a reinforcement matrix, adistal end cap and an embedded prosthetic connector in the distal endcap;

[0035]FIG. 23 schematically illustrates a procedure to dispense apredetermined quantity of uncured silicone elastomer into the closed endof the preformed assembly illustrated in FIG. 23;

[0036]FIG. 24 shows a cold forging system utilizing a female mold cavityand a male mold element that are brought together to form a mold cavityinto which previously inserted uncured silicone elastomer is cold forgedto completely fill the mold cavity;

[0037]FIG. 25 shows the die system illustrated in FIG. 24 in a closedcondition; and

[0038]FIG. 26 shows the detail XXVI in FIG. 25.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

[0039]FIG. 1 schematically illustrates in a cross-section view aprosthetic suction liner 10 that may be formed using the process andapparatus described herein. The liner is formed in part of a compositeelastic material 12 on its interior surface and an elasticized fabriclayer 14 on its exterior surface at least up to its distal end area 16,where a distal end cap 18 having embedded therein a rigid prostheticconnector 20 formed, for example, of aluminum or other metal, or rigidplastic such as Nylon, is provided.

[0040] The liner 10 is formed as a close ended tapered tubular element,as is conventional for such suction liners. The distal end cap 18 firmlyjoins the prosthetic connector 20 to the suction liner 10 whileproviding a cushioning and stabilizing surface at the distal end of theliner. The prosthetic connector 20 includes preferably a threadedaperture 22 for providing access to a threaded prosthetic pin connectorin a manner well known in the art.

[0041]FIG. 2 shows the suction liner in an end view as seen from thedistal end of the liner.

[0042]FIG. 3 is a cross-section view taken along line III-III of FIG. 1and shows the composite elastic material 12, the elasticized fabriclayer 14, and a second thin continuous coating of silicone elastomermaterial 24 partially embedded in the elasticized fabric layer 14 whilenot completely penetrating the fabric layer. The intermediate coating 24is bonded on its opposite side to the composite elastic material 12,whereby the entire assembly of composite elastic material 12, elastomercoating 24 and elasticized fabric 14 is at least freely radiallyelastically distendable.

[0043] The composite elastic material layer 12 may have embedded thereina matrix of reinforcement fibers 26 or other suitable reinforcementhaving properties such that the composite elastic layer 12 stronglyresists longitudinal elongation while it is freely distendable radiallyof the suction liner for use in liner applications when axial elongationof the liner must be limited. A circular knit glass fiber or Nylonmaterial is preferred.

[0044]FIG. 4 is an enlarged view of FIG. 3 and shows the compositeelastic material made in accordance with the present invention in moredetail as well as a wall section of suction liner 40 made with suchmaterial. Layer 12 may be a novel composite elastic material comprisinga cured silicone elastomer containing silicone oil and hollowmicrospheres 28 dispersed throughout the silicone elastomer layer.

[0045] The illustrations in FIGS. 3 and 4 also show the reinforcementmatrix fibers 26 embedded in the silicone elastomer layer, but it shouldbe understood that such reinforcement fibers are optional and extendover a distal portion of the liner to limit axial distension of theliner in such distal portion. The reinforcement fibers 26, of course, donot constitute a portion of the basic composite elastic materialdescribed above.

[0046] More specifically, the composite elastic material layer 12 itselfis regarded as a new and useful proprietary composite elastic materialindependently of the fibers 28, the outer fabric 14 and the intermediatecoating.

[0047] In a preferred example, the composite elastic material 12 isformed principally of a silicone elastomer obtainable from NuSilTechnology of Carpinteria, Calif. under Product Designation CF13-2188.For a fuller description of the silicone material, reference may be madeto pending U.S. Pat. No. 6,136,039 granted Oct. 24, 2000 owned by theassignee of the invention described herein.

[0048] Embedded within the silicone elastomer material of layer 12 arehollow thermoplastic microspheres consisting of a polymeric shell withan enclosed blowing agent. The specific thermoplastic microspheresutilized in this example of the invention are expanded microspheresobtained from AKZO NOBEL of Sweden under the trade name EXPANCEL®,Product No. 551 DE.

[0049] The microspheres 28 preferably have a density of 0.005 g/cm³ to1.25 g/cm³, preferably 0.05 g/cm³.

[0050] For a fuller understanding of the formulation of EXPANCEL®microspheres, reference may be made to EXPANCEL® Technical Bulletin 29and the EXPANCEL® product specification and material safety data sheets,all of which are available from AKZO NOBEL, S-850, 13 Sundsvall, Sweden.

[0051] The silicone oil included in the composite elastic material maybe obtained from GE Bayer Silicones GmbH of D 51 368 Leverkusen, Germanyunder Product Name Baysilone Fluid M350.

[0052] In a preferred form, the composite elastic layer 12 comprises50-99.4% by weight of silicone elastomer, preferably 77.25%; 0.5-45% byweight of silicone oil, preferably 10%; and 0.1-5% by weight ofmicrospheres, preferably 0.75%.

[0053] The composite elastic layer 12 also may include one or more skintreatment agents blended into the silicone elastomer, for exampleVaseline and aloe vera. In a preferred example, up to 20% by weight ofthe composite elastic layer, preferably 11.9%, may be Vaseline and up to3%, preferably 0.1%, may be a secondary skin treatment agent such asaloe vera.

[0054] While EXPANCEL® hollow microspheres as described above arepreferred, it should be understood that other hollow microspheres havinga density range of 0.005 g/cm³ to 1.24 g/cm³, preferably 0.05 g/cm³,could be used.

[0055] When prepared as described above, a preferred embodiment of thecomposite elastic layer will have a density of 0.5 g/cm³ to 1.3 g/cm³,preferably 0.94 g/cm³; a tensile strength greater than 0.1 Pa,preferably greater than 0.5 Pa; a durometer (00) of 13 to 62, preferably22; a 100% modulus of 5 kPa to 250, preferably 20 kPa; and a compressionset of 0 to 30, preferably 8.

[0056] It should be understood that different or additional skintreating agents may be utilized, depending upon the skin condition to betreated by the skin treating agent. For use as a typical suction sleeve,Vaseline and aloe vera are believed to provide good properties for thecomposite elastic layer that typically directly contacts or is in closeproximity with the skin of a prosthetic user.

[0057] When the composite elastic material 12 is laminated or bondedwith an elasticized textile layer 14, such layer 14, in a preferredembodiment, may be described as a Supplex Nylon circular knit of 87%Nylon, 13% Spandex fibers using 28 needles per 2.5 cm having a weightper square yard of 6.9 ozs. and a weight per linear yard of 12 ozs. Sucha Supplex Nylon is obtainable from Agmont Inc. of Montreal, Quebec,Canada under Style Name 5095. This material has a finished width of 60″(152.4 cm) and is substantially elastically distendable along its lengthand width in a manner appropriate for a prosthetic suction liner.

[0058] The reinforcing fibers 26 may be a circular knit textile formedof relatively non-distendable interlocked fibers (at least within theload ranges contemplated for use in a prosthetic suction liner) whereinthe knit construction is such that the layer 26 strongly resistselongation in a longitudinal direction while being freely distendablelaterally in a radial direction when it is embedded in the compositeelastic layer 12. Any appropriate reinforcement matrix that wouldprovide such properties could be used for layer 26, but as a practicalmatter a circular knit glass fiber or Nylon material is appropriate,provided it has the anisotropic properties described above.

[0059] The textile layer 14 is normally air permeable and is usuallyformed from a flat knit elasticized fabric that has been rolled into atube and stitched along abutting side edges along the length of thetube. The inside surface of the fabric layer 14 facing the compositeelastic layer 12 is coated with a thin layer of cured silicone elastomer24 that is partially embedded in the fibers of the textile 14 withoutcompletely penetrating the textile 14. The silicone elastomer layer 24is cured while embedded in the textile so that it is firmly adhered tothe textile and preferably renders the textile and silicone layer 24impermeable to air. The thin coating of silicone elastomer 24 provides agood bonding surface for the composite elastic layer 12 described above.

[0060] Preferably, the silicone layer 24 is obtainable under Product No.CF15-2188 from NuSil Technology of Carpinteria, California. Physicalproperties of the combined composite elastic layer 12, coating 24 andelasticized fabric 14 include a tensile strength greater than 1 Pa,preferably greater than 2 Pa; and a 100% modulus of 5 to 300 kPa,preferably 55 kPa.

[0061] The distal end cap 18 may be formed of a silicone elastomerincluding 98% by weight silicone rubber, type MED-4950 or type MED-4050or type CF15-2188, all available from NuSil Technology, with the balance(2%) constituted of a color mixture, for example a color powder blendedfrom 12.5 parts Lucas color No.2408,12.5 parts Lucas color No. 2439 and75 parts Lucas color No. 2510 all obtainable from Fr. Schoenfeld GmbHand Co. include: the material uses a platinum cure system; a press curetime of 50 minutes at 150° C.; durometer 45-55; tensile strength 1000psi (6.9 Mpa); elongation 400%; and a tear strength 230 ppi (40.3 kN/M).

[0062] As illustrated in FIG. 5, a sealing sleeve 30, for example asleeve capable of sealing the gap between the upper end of a prostheticsocket and a residual limb as illustrated in U.S. Pat. No. 5,571,208includes an outer textile layer 32 that is an elasticized, porous or airpermeable fabric on which a continuous cured silicone coating 34 hasbeen applied and bonded thereto in the same manner as the coating 24attached to the layer 14 of the suction sleeve material as illustratedin FIGS. 1-4 and described above.

[0063] The interior surface of the sleeve 30 includes a compositeelastic material 36 formed in the same manner as the composite elasticlayer 12 illustrated in FIGS. 1-4 and described above. The thickness ofthe composite elastic material 36 may be adjusted to fit therequirements of a sealing sleeve. The composite elastic layer 36 isintimately bonded and adhered to the coating 34. The combined assemblyof the textile 32, coating 34 and composite elastic layer 36 is fullydistendable both radially and longitudinally in accordance with therequirements of a sealing sleeve for prosthetic applications.

[0064] The outer fabric layer 32, in a preferred embodiment, may be acircular rib knit fabric made of 95% Nylon and 5% Lycra, knit as a 1×1rib using 220 needles per 2.5 cm for a 12 cm width tube and 264 needlesper 2.5 cm for a 14 cm tube. This fabric may be obtained from RX-Textileof Monroe, N.C.

[0065] A preferred form of the suction liner made with the compositeelastic material layer 12 is illustrated in FIGS. 6-10 (the fabric isomitted in the views as being nonessential). The composite elasticmaterial including the cured silicone elastomer layer with silicone oiland hollow microspheres and outer fabric is molded or formed as atapered suction liner 40 having a closed distal end 42 of uniformthickness, an external profile 44 (see FIG. 10) that is circular withthe radii of curvature of the external surface 44 centered on a firstcentral longitudinal axis 46 extending through the suction liner 40. Thegeometry of such suction liner is illustrated in FIGS. 6-10. Moreover,the following table 1 describes the variables shown in FIGS. 6-10 andalso describes typical values of some of the variables for differentsize suction liners listed in the left column of the table entitled“Typical Values of Variables”. TABLE 1 VARIABLE DESCRIPTION Variablename Description Angle Angle of socket opening H_fl_prox Height offlange in proximal area HH1 Height to flange in distal area HH2 Heightof flange in distal area HH3 Height of second cut HHtot Total height ofsocket Hst Height from radius to start of distal flange Offset Offset inlathe Rrad1 Radius on Distal end RRad2 Radius on proximal end ThaThickness in anterior area Thp Thickness in posterior area ThtopThickness of socket in top

[0066] TYPICAL VALUE OF VARIABLES Size Rrad1 HH1 HH2 HH3 Hhtot RRad2 ThaAngle Hfh prox Offset Thp Hst Thtop 12 19 rrad1 + Hst 80 Hhtot-HH1-Tha450 44.1 6 3 40 3 3 20 1 14 22.5 rrad1 + Hst 80 Hhtot-HH1-Tha 450 48.1 63 40 3 3 20 1 16 25.5 rrad1 + Hst 80 Hhtot-HH1-Tha 450 51 6 3 40 3 3 201 18 28.5 rrad1 + Hst 80 Hhtot-HH1-Tha 450 53.8 6 3 40 3 3 20 1 20 31.5rrad1 + Hst 80 Hhtot-HH1-Tha 450 56.7 6 3 40 3 3 20 1 21 33.5 rrad1 +Hst 80 Hhtot-HH1-Tha 450 58.6 6 3 40 3 3 20 1 22 35.5 rrad1 + Hst 80Hhtot-HH1-Tha 450 60.5 6 3 40 3 3 20 1 23.5 37.5 rrad1 + Hst 80Hhtot-HH1-Tha 450 62.4 6 3 40 3 3 20 1 25 40 rrad1 + Hst 80Hhtot-HH1-Tha 450 64.7 6 3 40 3 3 20 1 26.5 42.5 rrad1 + Hst 80Hhtot-HH1-Tha 450 67.1 6 3 40 3 3 20 1 28 45 rrad1 + Hst 80Hhtot-HH1-Tha 450 69.5 6 3 40 3 3 20 1 30 48 rrad1 + Hst 80Hhtot-HH1-Tha 450 72.3 6 3 40 3 3 20 1 32 51 rrad1 + Hst 80Hhtot-HH1-Tha 450 75.1 6 3 40 3 3 20 1 34 54 rrad1 + Hst 80Hhtot-HH1-Tha 450 78 6 3 40 3 3 20 1 36 57 rrad1 + Hst 80 Hhtot-HH1-Tha450 80.8 6 3 40 3 3 20 1 38 60.5 rrad1 + Hst 80 Hhtot-HH1-Tha 450 84.2 63 40 3 3 20 1 40 64 rrad1 + Hst 80 Hhtot-HH1-Tha 450 87.5 6 3 40 3 3 201 42.5 67.5 rrad1 + Hst 80 Hhtot-HH1-Tha 450 90.8 6 3 40 3 3 20 1 4571.5 rrad1 + Hst 80 Hhtot-HH1-Tha 450 94.6 6 3 40 3 3 20 1

[0067] The suction sleeve 40 includes a circular curved inside anteriorwall portion 50 having first radii of curvature centered on a secondlongitudinal axis of anterior curvature 52 extending longitudinallythrough the suction sleeve towards the anterior side of the firstcentral axis 46 and a posterior wall portion 54 having second radii ofcurvature centered on a third longitudinal axis 56 located in theposterior direction relative to the central axis 46, said first, secondand third longitudinal axes 46,52 and 56 all lying in a commonlongitudinally and transversely extending imaginary plane 60 (FIG. 10)bisecting the anterior and posterior wall portions 50,54 and wherein thesecond and third axes 52 and 56 are spaced apart a predetermined offsetdistance from each other on opposed sides of the first axis 46. Thus,this arrangement produces a posterior wall that is thinner than theanterior wall as shown in FIG. 10.

[0068] The anterior and posterior wall portions 50,54 intersect eachother along inner diametrically opposed transition wall portions 62 thatextend tangentially relative to the adjoining anterior and posteriorwall portions along the sleeve length, so that the interior wall surfaceof the suction liner along the transition areas 62 are free of rapidchanges in thickness, curvature or cross-section profile, as seen bestin FIG. 10.

[0069] In the example illustrated, the radii of curvature of the insidesurfaces of the anterior and posterior portions of the sleeve are equalto each other along their respective second and third axes, asobservable in FIG. 10. A formula for generating the interior profile ofthe suction sleeve shown in FIGS. 6-10 is indicated at the bottom ofFIG. 6, and such formula is used to control a computer assisted machinetool (e.g., lathe) used to form a male mold element that shapes theinner profile of the liner.

[0070] At the proximal area of the suction sleeve 40 (the open end ofthe sleeve) a flange area 66 is provided wherein the thickness of thecomposite elastic material progressively thins as the top edge 68 isapproached. The inside surface of the flange portion 66 of the anteriorwall 50, as seen in FIG. 9, tapers inwardly as the top edge 68 isapproached as shown at 70 and the outer surface of the proximal end ofthe flange portion 66 of posterior wall 54 also tapers inwardly as shownat 72 in FIG. 9. Preferably, the top edge 68 of the sleeve is relativelythin as compared with the thickness of the remainder of the sleeve.

[0071] The distal end 42 of the sleeve is spherical in curvature andjoins the adjoining side wall of the sleeve along a tangent so as toprovide a smooth interior and exterior contour as the sleeve transitionsbetween the tapered conical upper portion and the spherically curvedclosed end portion 42. The thickness of the end portion 42 may be thesame thickness as the anterior wall 50. The posterior wall 54transitions from the same thickness as the anterior wall at the distalend of the sleeve to a thinner wall section over the length of thesleeve in which the thinner wall section is desired. A smooth transitionarea 74 is provided between the thinner posterior wall section 54 andthe full thickness of the wall portion of the sleeve at the distal endof the sleeve.

[0072] The suction liner as illustrated in FIG. 1 may be made inaccordance with the process described below using the apparatus alsodescribed below for carrying out the process.

[0073] A textile layer corresponding to layer 14 is initially made as aflat strip 100 as illustrated in FIG. 11. The flat strip is rolled intoa tubular form so that opposed side edges of the strip are abuttedtogether and then stitched at 102 along the abutting edges to formcontinuous lengths 101 of tubular elasticized fabric that may beutilized in the external cover of a suction liner such as suction liner10.

[0074] A continuous film casting device for coating the tubes 101includes a vertically extending rod 103 having a conduit 104 extendingtherethrough in communication with a suction pump 106, the operation ofwhich is controlled by a controller element 107 in a manner to bedescribed in more detail below.

[0075] Along the length of the vertical rod 103, there is provided acasting zone 105 along which is located continuous annular film castingdevice 108 through which an uncured tubular elastomeric film or layermay be expressed as a continuous, generally vertical uninterrupted filmgenerally coaxially surrounding the rod 102 or any substrate materialthat may be advanced along the surface of the rod 102 through the filmcasting device 108.

[0076] A source 110 of coating material to be expressed through the filmcasting device 108 is connected to the latter by means of conduit 112,pump 114 and a control system 116 for governing the operation of thepump 114.

[0077] The film casting device 108 may be provided with a heating andcooling system 118, which may include a circulating system forcirculating a heating or cooling medium through the film casting device108 by means of a pump 120 governed by a control system 122.

[0078] A suction or sub-atmosphere chamber 124 is connected to the uppersurface of the film casting device 108 to create a sub-atmosphericpressure chamber 126 when a suction is applied to the chamber 126 viaconduit 128. The conduit 128, for example, may be connected to suctionpump 106 via conduit 104 during operation of the film casting device tocreate a sub-atmospheric pressure in chamber 126, or a separate suctionline 109 may be used for this purpose.

[0079] The lower end of the rod 102 extends through a heating or curingzone including heating furnace 130 which may contain, for example,radiant or electrical heating elements 132 that provide a source of heatfor curing a film expressed through the film casting device 108.

[0080] Annular tension control washers 136 spaced axially along thelength of rod 102 are provided to control tension of a substrate coatedin the apparatus described in a manner to be explained in more detailbelow.

[0081] An annular array of suction orifices 140 or the equivalent areprovided on the rod 102 and which are in communication with air passages144 which are in turn in communication with air passage 104 within rod102. Orifices 140 may be incorporated in an annular member affixed tothe rod 102 at a location where apertures 144 are provided in the rod102 enabling communication between the orifices 140 and the passage 104.Suction applied by pump 106 can thereby be applied at orifices 140 overan area surrounding the rod 102.

[0082] Textile advancing drive elements 150 are provided adjacent therod 102 above the suction housing 124 for cooperating with a relativelyfixed guide element 152 affixed to rod 102. The drive element 150 isrotatable by a motor 154 operable under the control of a controller 55connected to the motor. When a substrate is inserted between the driveelement 150 and the seat 152, the substrate will be advanced along therod 102 in accordance with the driving direction of the rotatableelement 150.

[0083] The orifices in film casting device 108 for expressing ordischarging a tubular film or coating material 155 supplied from source110 is configured in accordance with desired properties of the film orcoating to be applied by the coating system as shown. Relatively thincoatings may be expressed through a continuous annular slot provided inthe film casting device 108 or relatively thick coatings may be appliedin the same fashion.

[0084] The vacuum in chamber 126 is adjusted to provide initial contactbetween a film 155 expressed through the film casting device 108 and thesubstrate advanced through the film casting device in a manner to bedescribed below. Subsequently, when the substrate is air permeable, thesuction device 140 draws the uncured film material into the substrate toa desired extent, for example only partially through the substratethickness if it is desired to maintain uncoated substrate on the opposedsurface of the substrate advanced through the film casting device.Higher suction applied at suction device 140 could be applied if it wasdesired to fully penetrate a porous substrate advance through the filmcasting device.

[0085] The heater 130 is regulated to fully cure a film expressedthrough the film casting device 108 and the time and temperature of suchcuring may be regulated by regulating the speed of advancement of thecoated substrate through the heating device in accordance with knownprinciples related to curing of curable films in coatings such assilicone elastomer, for example.

[0086] The operation of the film casting system as shown in FIG. 12 willnow be explained in the context of coating an elasticized tubular fabricwith a cured silicone elastomer film. A previously formed length oftubular, elasticized fabric such as porous or air permeable fabriclength 101 is threaded vertically upwardly over rod 102 with a lower endof the fabric threaded over element 152, through suction chamber 126,through the film coating device 108, over suction device 140, throughheater 130 and onto a take-up spool 160 that is rotatable at acontrolled speed by motor 162 in accordance with signals received fromcontroller 164. Idler rollers 166 may be provided to enable thedirection of the coated fabric to be turned at the lower end of rod 102to advance the fabric to the take-up spool 160.

[0087] With a length of fabric 101 thus threaded over rod 102, thefabric is drawn at a controlled speed downwardly over the rod 102 whilesuction chamber 106 is activated and an uncured tubular siliconeelastomer resin film is expressed outwardly as a thin annular sheet offilm from casting device 108 towards the fabric 101 that is drawnthrough the film casting device 108. Initially, the inner edge of thefilm expressed through the film casting device 108 may be manuallyadhered to the surface of fabric 101, whereupon the film 126 effectivelycloses the bottom of the suction chamber 126 so that the film isthereafter drawn inwardly by sub-atmospheric pressure communicated tothe outer surface of the fabric 101 via the interstices of the fabricagainst the surface of the fabric uniformly over its entire periphery asthe fabric is advanced through the film casting device 108.

[0088] The fabric is threaded through the advancing mechanism 150,152 byrotating the roller 150 in a direction to advance the fabric downwardlyover the rod 102. The positive feeding of the fabric 101 through thesuction device 126 prevents undue tension from being applied to thefabric upon rotation of the take-up spool 160. It is desirable tomaintain the fabric substrate in a relatively relaxed condition to theextent possible, although a pretension may be applied to the fabric ifdesired as it is advanced through the film casting device 108 or throughthe heater 130.

[0089] The suction device 140, as shown in detail in FIG. 14, draws theuncured and pliable continuous, uninterrupted elastomeric film layerintimately into contact with and adhered to the air permeable substratefabric 14 to the extent desired for the specific application of thecoated fabric.

[0090] The fabric with the uncured resin coating then passes through theheater 130 where the coating is cured for a desired time at a desiredtemperature, all dictated by the properties of the cast film to becured, and in accordance with known principles.

[0091] Within the heater 130, the tension on the coated fabric iscontrolled by the annular tension control washer elements 136 whichapply a predetermined frictional drag on the fabric on its inner side asit is advanced over the rod 102 and also maintain the fabric extendedradially somewhat as it passes through the heater 130. The number ofannular elements 136 may be adjusted in accordance with the fabric andthe coating applied thereto.

[0092] The film casting device 108 may be selectively heated or cooledby using the heating and cooling system illustrated at 118,120,122. Thedegree of heating or cooling will depend upon the composition of thefilm to be cast on the surface of the fabric 101.

[0093] The resultant coated tubular fabric collected on spool 160 is nowavailable to be used in a subsequent process to make a suction liner ormay be available for any other application wherein a continuous curedcoating applied to an elasticized tubular substrate is desired.

[0094] In this example, the film to be cast on fabric 101 corresponds tofilm 24 described previously and the fabric 101 corresponds to thefabric outer layer 14 of the silicone liner described above in FIGS.1-4.

[0095] After coating of the elasticized fabric 101 using the apparatusdescribed above, the coated fabric is cut into lengths as shown in FIG.15 and a length of tubular reinforcement matrix material 169 is affixed,for example by sewing, to the end of the coated fabric. The matrix 170may correspond to layer 26 in the suction liner of FIG. 1. Preferablythe reinforcement matrix comprises interlocked fibers such as a circularknit tubular fabric that strongly resist longitudinal elongation butreadily distends radially.

[0096] Individual lengths of the coated fabric and reinforcement matrixare then prepared to receive a distal end cap (to be described below)that will be molded to one end of the coated length of fabric 101 toclose said end and to embed a portion of the matrix 170 in the interiorof the coated tubular fabric, as will become evident following a reviewof the description of the distal end cap molding apparatus shown in FIG.16.

[0097] The coating apparatus described above may be used to formmultiple continuous coatings on a tubular substrate simply by advancinga previously coated tubular substrate through the coating apparatus inthe same manner as described above. For example, the sealing sleeveillustrated in FIG. 5 may be formed using the coating apparatusillustrated in FIG. 12 by first providing a continuous coating ofsilicone elastomer on one surface of a tubular elasticized fabric andthen subsequently passing the thus coated fabric through the filmcasting device 108 while expressing a composite elastic materialcorresponding to layer 36 in FIG. 5 through the casting device 108. Thelayer 36 may then be cured in the heater 130.

[0098] In FIG. 16, a compression molding apparatus is illustrated foruse in molding a distal end cap on one end of a length 101 of coatedelasticized fabric with a reinforcement matrix 169 attached thereto. Themolding apparatus includes a lower female mold cavity 170 configured toform an external shape on a distal end cap to be molded in the cavityand including a central guiding aperture 172, heating elements 174,preferably electrically energized, and a pressure chamber 176 that is incommunication with a pneumatic pump 178 that is controllable bycontroller 180 in combination with a shut-off valve 182 that selectivelypressurizes pressure chamber 176. Pneumatic pressure orifices 184 arespaced peripherally around the support 186 for the female mold 170.

[0099] The support 186 is rotatably mounted on a base 187 by means ofbearings 188 so that the female mold support 186 may be rotated about anaxis of rotation relative to the base 187 and the upper part of themolding device to be described below. Vertical support members 189 areschematically illustrated extending between the base 187 and the upperpart of the molding device. The support members 189 may be rods orpillars with open areas between them to provide access to the femalemold 170 and the upper part of the molding device.

[0100] The upper part of the molding device supported above the femalemold 170 includes a male mold plug and clamping element 190 and acooperating clamping cylinder 192 that slidably supports the male moldand clamping device 190 for reciprocal movement relative to the clampingcylinder 192. The mold and clamping device 190 is supported, forexample, by a rod 194 or equivalent that is connected to a pneumaticcylinder 196 that is operable to control movement of the male mold andclamping element 190 towards and away from the distal end of theclamping cylinder 192 to effectively open or close the distal or lowerend of the clamping cylinder 192.

[0101] The interior of clamping cylinder 192 is provided with a suctionchamber 196 that communicates with a suction pump 198 via conduit 200and shut-off valve 202. Pump 198 and shut-off valve 202 are operatedunder the control of a controller 204 such that a suction can be appliedto suction chamber 196 by pump 198 selectively to create an inflow ofair between the mold and clamping device 190 and the distal end of theclamping cylinder 192 through a gap 195.

[0102] The entire assembly of the clamping cylinder 192 and the mold andclamping device 190 may be reciprocally moved towards and away from thefemale mold 170 by a second pneumatic or hydraulic cylinder 208, theoperation of which is controlled by a controller 210 and appropriatevalving 212, whereby the clamping cylinder 192 and the mold and clampingdevice 190 may be advanced into cooperation with the female mold 170 tocreate a mold cavity between the bottom surface of the mold and clampingdevice 190 and the surface of the female mold 170.

[0103] A guide rod and orifice plug 214 optionally extends centrallythrough the male mold and clamping device 190 for cooperation with theguide opening 172 in the female mold 170 when it is desired to maintainan aperture in a distal end cap to be molded between the male and femalemolds 190,170. Such an aperture is desired if a prosthetic connector isto be molded into the end cap.

[0104] The various pumps, valves and controllers, as well as the heatingelements 174 all may be controlled and operated from a central controlpanel 220 using conventional control technology including digitalcomputer processors.

[0105] The operation of the molding device described in FIG. 17 will nowbe described in conjunction with FIGS. 18-22 when it is desired to moldan end cap on a coated elasticized fabric with a prosthetic connectorand a distension controlling reinforcement matrix as previouslydescribed. Initially, a length of the coated elasticized fabric 101 witha reinforcement matrix 169 attached thereto as shown in FIG. 15 isthreaded over the female mold support 186 with the free end of thereinforcement matrix 170 threaded over the distal end area of theclamping cylinder 192, as illustrated in FIG. 17. The mold and clampingdevice 190 is in the extended position thereby exposing the gap 195between the mold and clamping device 190 and the distal end of clampingcylinder 192. A suction is then applied to the suction chamber 196 bypump 106 which draws in the free end of the reinforcement matrix 170through the gap 195.

[0106] The mold and clamping element 190 is then moved to its upper orclosed position relative to the clamping cylinder 192 to effectivelyclose the gap 195 and to clamp the free end of the reinforcement matrix170 between the mold and clamping device 190 and the clamping cylinder192, as illustrated in FIG. 18.

[0107] The female mold support 186 is then rotated ¼ turn or so relativeto the base 187 to introduce a twist constriction 218 in the tubularreinforcement matrix 170 that effectively forms a closure at the one endof the length of coated elasticized fabric 101 and leaves a free tubularlength of reinforcement matrix 170 within the clamping cylinder 192. Therod element 214 in this example extends through the central area of thetwisted section 218 of reinforcement matrix 170.

[0108] As shown in FIG. 20, a sudden pressure is then applied topressure chamber 176 that blows the length of coated elasticized textileoutwardly and upwardly over the external surface of the clampingcylinder 192, which may be provided with suction orifices 219 to assistin this procedure as seen in FIG. 20.

[0109] A rigid prosthetic connector “umbrella” element 224 is nextprimed or coated with an uncured elastomer that forms an intimate bondwith the connector element and with the elastomer to be used for thedistal end cap to be molded in the cavity to be provided between themale mold and clamping element 190 and the female mold 170. The thusprimed and coated prosthetic connector element 224 is placed in thefemale mold 170 so that it is spaced away from the bottom of the moldsurface with a connector portion thereof 226 extending through aperture172. A premeasured portion 225 of uncured elastomer material (which maybe the same as the primer) is then placed in the female mold cavity 170on the connector element 224 and thereafter the clamping cylinder 192and the associated mold and clamping device 190 with the coatedelasticized fabric 101 and reinforcement matrix 170 is advanced towardsthe female mold 170 to compress and shape the uncured elastomer materialin the mold cavity so that it conforms on one side to the surface of thefemale mold 170 and on its other side to the surface of the male moldand clamping element 190. In this process, the prosthetic connector 224becomes totally embedded in the silicone material in the mold cavity sothat it is completely covered by the elastomer. This is illustrated inFIG. 21, for example.

[0110] The heater element 174 is activated at the appropriate time toheat the female mold 170 to an appropriate curing temperature for thesilicone elastomer used to form the distal end cap and the primingelastomer applied on the prosthetic connector 224. The elastomer is thencured to produce a relatively firm distal end cap 230 as shown in FIG.23, with a free length of reinforcement matrix 170 within the coatedelasticized fabric 101. The distal end cap 230 bonds together thetwisted reinforcement matrix 218 while the male and female moldingsurfaces together shape the inside and outside contours of the distalend of the coated fabric 101. The elastomer selected for the end cap 230provides desired properties forthe distal end cap as part of aprosthetic suction liner.

[0111] The pre-formed assembly of coated tubular elasticized fabric 101,end cap 230 and reinforcement matrix 170 are then placed in a holder 234as shown in FIG. 23 to expose the internal distal end of the length ofcoated fabric 101 and the reinforcement matrix 170 so that apre-measured quantity of uncured elastomer liner resin material 232, forexample, a silicone elastomer corresponding to the composite elasticmaterial 12 shown in FIG. 1, can be dispensed into the open distal endas shown in FIG. 24. A source of the silicone elastomer resin isprovided at 236 and a precision measuring pump 238 is operated viacontroller 240 to dispense a precise quantity of uncured elastomer 232into the holder 234 and within the open distal end of the length oftubular elasticized fabric 101 that has been closed by the end cap 230.

[0112] The partially filled pre-form is now placed in a female moldingor shaping die cavity 242 as shown in FIG. 24 with the length of coatedfabric 101 fully extended over the length of the female die cavity 242.The female die cavity 242 is defined within a female die supportstructure 244 that may include suction orifices 246 to which a suctionmay be applied via valve 248 to draw the pre-formed coated elasticizedfabric 101 and the distal end cap 230 into close conformity with thefemale die cavity 242. The support 244 includes a heater 250 that may beenergized to raise the temperature of the female die support up to thecuring temperature of the elastomer deposited in the distal end of thecoated fabric sleeve 14.

[0113] A male die element or plug 252 is reciprocally mounted relativeto the female die support 244 so as to be axially movable into and outof the cavity defined by the female die 242. A pneumatic or hydrauliccylinder arrangement 254 may be provided to advance the male die element252 towards and away from the female die cavity 242 under the control ofa controller 256 that may be integrated with the controller for theheater 250.

[0114] The external contour of the male die 252 is configured to providea defined shape to produce a die cavity that results when the male die252 is fully advanced towards the female die cavity 242 to form a diecavity as shown in FIG. 25. As the male die 252 advances into female diecavity 242, the uncured elastomer 232 is cold forged or driven into thedie cavity between the male die 252 and the inner walls of the femalecavity 242 progressively from the distal end of the pre-formed coatedfabric and distal end cap to the proximal open end of the tubular fabric101. The external surface of the male die 252 is contoured to define theinternal shape of the elastomer material occupying the die cavitybetween the male die 252 and the female die cavity 242 while the femaledie cavity 242 is shaped to define the external contour of the fabric101 to be joined with the elastomer in the mold cavity. The contour ofthe male die 252 also includes appropriate surface areas designed toenhance the uniform flow of uncured elastomer from the distal end of thepre-form to the proximal end thereof to ensure that the die cavitybetween the male and female die elements is completely and uniformlyfilled with the uncured elastomer material that previously wasintroduced into the tubular elasticized fabric 101 in a quantitysufficient to fill the die cavity.

[0115] To assist in guiding the length of coated fabric 101 into thefemale die cavity 242, a guide pin 253 having a threaded proximal endmay be threaded into the prosthetic connector 224 prior to insertion ofthe fabric length 101 into the female die cavity. An aperture 253′ isprovided in the bottom of the support 244 to receive the guide pin 253as the fabric length 101 is lowered into the female die cavity.

[0116] To assure uniform lengths of finished cold forged products, alocking ring 251 may be provided at one end of the fabric sleeve 101that cooperates with the male die 252 to limit the length of the coldforged liner formed from the uncured silicone elastomer 232 when themale and female dies are brought together.

[0117] The heater 250 is activated at the appropriate time to cure theelastomer 232 in the die cavity for an appropriate length of time and atan appropriate temperature in accordance with the elastomer materialselected to fill the mold cavity. Heaters 257 may be used in the maledie 252 as well.

[0118]FIG. 26 shows an enlargement of a detail of the female die cavity242, the heater 250, the coated fabric 101, the coating 155 on thefabric and the innermost layer 232 of elastomer containing an embeddedreinforcement matrix and the position of the male die 252. Upon curingof the elastomer in the mold cavity, the male die 252 is withdrawn andthe now fully integrated assembly of fabric 101, elastomer coating 155,and innermost elastomer layer 232 is removed from the female mold 242.The guide pin is then removed, leaving a fully formed suction linercorresponding to suction liner 10 in FIG. 1 ready for final detailingand eventual use.

[0119] When the innermost layer of elastomer 232 is constituted of thecomposite elastic material described above in connection with FIGS. 1-4,the male and female dies may be heated to a temperature of 100° C. andthe elastomer may be cured for a cure time of 6 minutes.

[0120] The exterior contour of the male die 252 may be shaped inaccordance with the inner peripheral contour of layer 12 of suctionsleeve 10 as described in connection with FIGS. 6-10 as describedpreviously.

[0121] While a specific embodiment of the inventive process andapparatus constituting the inventive subject matter have been describedpreviously, it should be understood that various modifications to theprocess and apparatus can be made without departing from the spirit andscope of the invention.

[0122] The tubular fabric 101 may be produced in various lengths with orwithout a longitudinal seam and instead of a reinforcement matrix 170,any appropriate material can be utilized to form a twisting closure inthe apparatus shown in FIG. 16, including the fabric 101 itself if nomatrix is used.

[0123] The coating apparatus of FIGS. 12-15 may be utilized to coat anytubular material, including a non-porous or non-permeable tubularmaterial. When non-porous material is coated, the suction applied insuction chamber 126 is adjusted to ensure appropriate adhesive to theexterior surface of the moving tubular substrate and the suctionorifices 140 do not need to be used. Likewise, the tension controllingelements 136 may be adjusted to accommodate the specific tubularsubstrate to be coated in the apparatus.

[0124] The premeasured quantity of uncured silicone elastomer could bedirectly deposited into the open tube 101 after the latter has been setinto the female die cavity 242.

[0125] Other various departures from the specific embodiment describedabove can be envisioned within the skill of the person skilled in theart and it is to be understood that the specific steps and apparatusdisclosed herein are to be exemplary only.

I claim:
 1. A method for making a tubular member having a continuous anduninterrupted cured elastomeric resin coating on one of two opposedsurfaces of the tubular member comprising: forming a continuousvertically extending uninterrupted tubular layer of uncured elastomericresin; drawing the layer of resin against one of said surfaces of thetubular member to be coated by applying suction below atmosphericpressure between the resin layer and the said one surface of the tubularmember to which the resin layer is to be applied while continuouslymoving the tubular member relative to the continuously formed resinlayer with the tubular member generally vertically oriented and ingenerally coaxial relationship with the tubular layer of the elastomericresin until said one surface is coated with said uncured resin layer andsaid layer of uncured resin is adhered to said one surface; and curingsaid elastomeric resin while it is adhered to the one surface of thetubular member.
 2. The method according to claim 1, wherein said tubularmember consists of a material that is porous, comprising drawing thetubular layer of uncured elastomeric resin against the one surface to becoated by applying sub-atmospheric pressure to the surface of saidtubular member opposed to the surface to be coated by the tubular layerof uncured elastomeric resin to thereby create a sub-atmosphericpressure condition across the porous material of the tubular member andbetween the tubular member and the uncured layer of elastomeric resin.3. The method according to claim 2, including drawing said uncuredelastomeric resin layer at least partly into the pores of the porousmaterial of said tubular member during said drawing step to therebyfurther adhere the uncured elastomeric resin layer to the one surface ofthe tubular member.
 4. The method according to claim 2 or 3, includingselecting an elasticized fabric as the material forming said tubularmember.
 5. The method according to claim 1, including selected asilicone resin as said uncured elastomeric resin layer.
 6. The methodaccording to claim 2 or 3, including selecting an elasticized fabricmaterial for use as the material of said tubular member.
 7. A tubularmember having a continuous and uninterrupted cured elastomeric resinlayer adhered to one of the opposed surfaces of the tubular member madeby the process according to any one of claims 1-6.
 8. A compositetubular member comprising a continuous length of a tubular member formedof porous material coated on one side with a continuous uninterruptedelastomeric resin layer that extends only partly into the pores of theporous material.
 9. A composite tubular member as claimed in claim 8,wherein the resin layer is silicone.
 10. A composite tubular membercomprising a continuous length of a tubular member formed of anelasticized porous fabric coated on one side with a continuousuninterrupted layer of cured elastomeric resin that extends only partlyinto the pores of the fabric.
 11. A resin coated tubular member asclaimed in claim 10, wherein said elasticized fabric is a tubular knitmaterial.
 12. A process for forming a length of a continuous tubularmember with an uninterrupted continuous layer of elastomeric resincovering and adhered to one of two opposing sides thereof, comprising:continuously feeding a tubular member in a generally longitudinal andvertically downward direction relative to and through a coating zonemaintained at a sub-atmospheric pressure; while carrying out saidfeeding step, applying and adhering a continuous, uninterrupted tubularuncured elastomeric resin layer to said one side of said tubular memberwithin said coating zone by applying sub-atmospheric pressure betweensaid elastomeric resin layer and said one side of said tubular member;and curing said elastomeric resin while it is adhered to said one sideof said tubular member.
 13. The process as claimed in claim 12, whereinsaid tubular member is formed of an air permeable material havinginterstices, further comprising supplying sub-atmospheric pressurebetween said elastomeric resin layer and said one side of said tubularmember by exposing the opposed side of said tubular member to saidsub-atmospheric pressure and communicating the sub-atmospheric pressureto the side of the tubular member to be coated via interstices of theair permeable member.
 14. The process as claimed in claim 12, includingselecting an air permeable material having interstices as the materialconstituting the tubular member, and further drawing the uncuredelastomeric resin layer at least partly into the interstices of the airpermeable material on said one side of the tubular member by applying asub-atmospheric pressure to the opposed side of the tubular member andcommunicating the sub-atmospheric pressure to the uncured elastomericresin layer via the interstices after the uncured elastomeric resinlayer has been adhered to one side of the tubular member.
 15. Theprocess as claimed in claim 12, 13 or 14, including the step ofselecting an elasticized fabric as the material constituting the tubularmember, and radially distending and longitudinally tensioning thetubular member during the curing step.
 16. Apparatus for applying acontinuous uninterrupted resin layer on one surface of a continuoustubular substrate, comprising: a coating zone including a continuousresin casting device arranged to dispense a continuous, uninterrupted,tubular coating material layer of uncured elastomeric resin into thecoating zone; said coating zone including a sub-atmospheric chamberarranged so as to provide a sub-atmospheric pressure within the chamberto which said coating material layer is subjected during operation ofthe apparatus; a heating zone located adjacent said coating zone, saidheating zone including a heater device; and a feed mechanism arranged toengage and feed a continuous tubular substrate along a longitudinaldirection of the substrate through said sub-atmospheric chamber andcoating zone, and said heating zone in the recited order.
 17. Apparatusas claimed in claim 16, including a vertically extending rod member;said rod member extending centrally through said sub-atmosphericchamber, coating zone and heating zone in the recited order; said rodmember arranged to support a tubular substrate to be coated along alength of said rod member extending through said sub-atmosphericchamber, coating zone and heating zone.
 18. Apparatus as claimed inclaim 17, said rod member including a conduit having a sectionterminating in said sub-atmospheric chamber and a device for supplyingsub-atmospheric pressure to said conduit.
 19. Apparatus as claimed inclaim 17 or 18, said rod member including a conduit having a sectionterminating at at least one suction orifice located at an external areaof said rod between the coating zone and the heating zone.
 20. Apparatusas claimed in claim 17, 18 or 19, including longitudinally spacedfriction washer elements disposed along said rod member, said washerscomprising annular members each having an outside diameter related to adesired inside diameter of a tubular member to be coated, at least oneof said washer elements disposed in said heater.
 21. Apparatus asclaimed in one of claim 16-20, said feed mechanism comprising driverollers disposed and arranged to frictionally engage the tubular memberand to advance the tubular member relative to and along said rod memberthrough said coating zone and heater.
 22. Apparatus as claimed in claim16, said resin casting device including a heating device arranged so asto provide heating energy to a resin material supplied to the castingdevice.
 23. Apparatus as claimed in claim 16, said resin coating deviceincluding a cooling device arranged so as to provide cooling energy to aresin material supplied to the casting device.
 24. A method for moldinga distal end cap on an open end of a length of a pre-formed tubularsleeve member formed of an elasticized fabric with a porous tubularreinforcement matrix integrated with said end cap, comprising the steps:providing a length of a pre-formed tubular sleeve member formed ofelasticized fabric and having an open end; securing a length of atubular reinforcement matrix element formed of interlocked fibers thatare arranged so the matrix member is porous and strongly resistselongation in the sleeve longitudinal direction but is readilystretchable in transverse radial directions to an open end of thetubular sleeve member so the sleeve member and matrix element extendgenerally coaxially; twisting the matrix element about its central axisadjacent the open end of the sleeve member to effectively close the openend of the sleeve member by the twisted matrix element; providing afemale mold having a female mold cavity dimensioned and configured tocorrespond with a desired outer contour of a distal end cap to be joinedto the sleeve member; placing a predetermined quantity of an uncured endcap elastomeric resin in the female mold cavity; providing a male moldelement dimensioned and configured to cooperate with the female mold sothat, when the male mold element located in molding relationship withthe female mold, a closed mold cavity defining the external contour of adistal end cap is formed; locating the portion of the matrix elementextending beyond the twisted portion inside the adjacent open end of thetubular sleeve; locating the male mold element inside the matrix sleeveportion located inside the tubular sleeve; advancing the male moldelement, matrix sleeve and tubular sleeve into molding relationship withthe female mold so that the twisted portion of the matrix elementextends within the closed mold cavity along with the uncured distal endcap resin so that the resin penetrates the porous material of the matrixelement and closes the open end of the sleeve member; curing the resinin the mold cavity; and removing the molded distal end cap andreinforcement matrix from the mold cavity, wherein the former open endof the sleeve member is closed by the molded distal end cap and thereinforcement matrix is located concentrically inside the end area ofthe sleeve adjacent the distal end cap.
 25. The method as claimed inclaim 24, said tubular sleeve including an inner wall, and includingproviding the inner wall of said tubular sleeve with a continuous,uninterrupted elastomeric resin film coating before molding said distalend cap to the open end of the sleeve member.
 26. The method as claimedin claim 24, including placing a rigid umbrella prosthetic connectorelement in said female mold cavity with said predetermined quantity ofuncured distal end cap resin and curing the distal end cap with theconnector element embedded in the distal end cap resin.
 27. A preformfor a prosthetic suspension sleeve comprising: a tubular sleevecomprising an elasticized fabric, said tubular sleeve including an openend; a distal end cap molded on and closing the open end of the tubularsleeve; a tubular matrix reinforcement element secured coaxially to theopen end of the sleeve member and having a portion embedded in thedistal end cap and a portion extending coaxially within the open endarea of the sleeve member.
 28. A preform as claimed in claim 27,including a prosthetic umbrella connector element embedded in the distalend cap.
 29. A preform as claimed in claim 27, said sleeve member havingan inner wall, and including a continuous, uninterrupted curedelastomeric resin film coating on the inside wall surface of said sleevemember.
 30. A preform as claimed in claim 29, wherein said film coatingand distal end cap comprise silicone elastomer material.
 31. A preformas claimed in claim 27, wherein said matrix reinforcement element iscircular knit fabric material selected from the group consisting ofglass fiber and Nylon.
 32. A process for forming a sleeve membersuitable for prosthetic applications, said sleeve members comprising atubular elasticized fabric element having a distal end cap attached toand closing one end of the sleeve element, comprising the steps of:placing a predetermined quantity of uncured elastomeric resin intendedto form said cured elastomer layer in the interior of the closed end ofthe sleeve member; placing the sleeve member and uncured elastomer resinin a female molding die cavity having an interior contour correspondingto the desired outer contour of said sleeve member; placing a male molddie member having an outer contour corresponding with the desired innercontour of the sleeve member within the sleeve member and advancing themale mold die member into the sleeve member and female mold die cavityuntil it reaches a molding position relative to the female mold diecavity, at which position a closed die cavity between the male mold diemember and the female mold die cavity is defined, said sleeve is locatedin the mold cavity adjacent inner walls female mold die and the uncuredelastomer resin occupies the remainder of the closed die cavity, saidresin having been distributed throughout the closed die cavity andagainst the interior of the sleeve member by movement of the male molddie member relative to the female mold die cavity and the uncured resin;said predetermined quantity of uncured elastomer resin being calculatedto fill said closed die cavity; curing the elastomer resin in the closeddie cavity in bonded relationship with the interior of the sleevemember; withdrawing the male mold die member, tubular sleeve member,distal end cap and cured elastomer layer from the female mold diecavity.
 33. The process as claimed in claim 32, including securing atubular reinforcement matrix member to the closed end of said sleevemember so that the matrix member extends loosely within the sleevemember adjacent the interior surface a of said sleeve member; saidmatrix member comprising interlocked fibers that are arranged so thatthe matrix member is porous and strongly resists elongation along thesleeve longitudinal direction but is readily stretchable in thetransverse radial direction; and the step placing said predeterminedquantity of uncured elastomer resin in the sleeve member includesplacing said quantity within the matrix member, whereby, upondistribution of said uncured elastomer resin within the closed diecavity by the movement of the male die member, said matrix member isembedded in the uncured elastomer resin material and is integrated withthe elastomer resin upon curing thereof.
 34. The process as claimed inclaim 32, including drawing said tubular sleeve member against theinterior wall of the female mold die cavity during advancement of themale mold die member into the female mold die cavity by using suction ofair from the area between the tubular sleeve and the female die cavityinterior walls.
 35. The process as claimed in claim 32, includingcovering the interior surface of said tubular sleeve member with acured, continuous, uninterrupted elastomeric resin layer prior toplacing said predetermined quantity of uncured elastomer resin in saidsleeve member, whereby said cured elastomeric resin layer seals theinterior surface of said elasticized fabric constituting said sleevemember prior to the placement of the sleeve member in the female moldingdie cavity, and whereby said uncured elastomer resin filling said diecavity is cured in bonded relationship with said continuous elastomericresin layer.
 36. The process as claimed in claim 32, including selectingsilicone resin as the uncured elastomer resin.
 37. The process asclaimed in claim 35, including selecting silicone resins for saidcontinuous layer of cured elastomer extending over the interior of saidsleeve member and for said uncured elastomer resin placed in theinterior of the closed end of the sleeve member.
 38. A preform for aprosthetic suspension sleeve comprising: a tubular sleeve comprisingelasticized fabric; iva tubular matrix reinforcement element securedcoaxially to the open end of the sleeve member, said matrixreinforcement element comprising interlocked fibers that are arranged sothat the matrix reinforcement element is porous and strongly resistselongation in the sleeve longitudinal direction but is readilyelastically stretchable in transverse radial directions; said tubularsleeve having an inner wall coated with an uninterrupted, continuouselastomeric layer.